JP2013092277A - Heat exchanger for air conditioning equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a heat exchanger for air conditioning to significantly increase heat exchange efficiency, to reduce the cost of manufacturing, and to obtain the uniform quality of products.SOLUTION: A main pipe 6 is embedded in the ground below a floor 1. A vertical partition wall 7 is integrally installed in the main pipe 6. These members are preferably formed of aluminum alloys. An air stream blown by a blower 5 in a direction of an arrow a flows in a direction of an arrow h to j and is discharged in a direction of an arrow k. During the downward flow along the arrow h and the upward flow along the arrow j, the flowing air is heat-exchanged with the ground through a pipe wall of the main pipe 6 and cooled in summer and heated in winter. Thereby, the air stream is cooled and heated in both the outward path (arrow h) and the return path (arrow j).

Description

  The present invention relates to a heat exchanger for an air conditioner, and more particularly, to a heat exchanger for obtaining a cold airflow and / or a warm airflow for an air conditioner by exchanging heat between soil and airflow near several meters below the ground. Is.

In the vicinity of several meters below the ground, a technology that obtains cool air in the summer and warm air in the winter by circulating the air underground, utilizing the fact that the temperature is kept constant regardless of the season or day and night. This technique is known and applied to a cooling / heating air-conditioning apparatus that uses a constant temperature underground.
In this way, air conditioning using natural heat has no fear of causing pollution or depleting resources.
Moreover, it does not generate noise like wind power generation, is not affected by the weather, does not sleep at night like solar power generation, and does not degrade performance due to cloudy weather, so it uses natural heat There is a great social demand for improvements in air conditioning.

  FIG. 6 is a schematic diagram showing a publicly known example of a heat exchanger for an air conditioner using underground cold / heat. Conventional heat exchangers for air conditioning equipment are generally configured as shown in FIG. That is, the outer cylinder 2 having a length of 4 to 5 meters is embedded in a vertical hole provided in the ground below the floor 1. An inner tube 3 is disposed concentrically in the outer cylinder 2. The lower end portion of the outer cylinder 2 is closed, and water for exchanging heat with the air flow fed in is stored as the reservoir water 4. The exhaust in the house is collected by the blower 5, sent out in the direction of arrow a, enters the inner tube 3 in the direction of arrow b, and descends through the inner tube 3 in the direction of arrow c. The air that has flowed down is blown to the accumulated water 4 to change the direction as indicated by the arrow d, and rises along the inner wall surface of the outer cylinder 2 in the direction of the arrow e. And the ventilation which passed through the outer cylinder 2 is discharge | released under the floor in the direction of arrow f.

As understood from FIG. 6, the air flow sent to the vicinity of the lower end of the outer cylinder 2 collides with the accumulated water 4 to remove dust, and then follows the inner wall surface of the outer cylinder 2 in the direction of arrow e. As it rises, it is heated in winter and cooled in summer. For example, according to observations at the Chiba Meteorological Observatory, the temperature at the surface of the subsurface 3 meters at the point where the monthly average temperature of the surface shows a change (annual) of 5 ° C to 30 ° C is 16 It was -18 degreeC.
The air flow adjusted to a temperature comfortable in this way is released in the direction of the arrow f and supplied to the room through the floor 1. In FIG. 6, reference numeral 2a denotes a heat transfer fin.

  In addition, as a specific example of a heat exchanger for an air conditioner, Patent Document 1 discloses that an outer tube whose end is sealed and whose other end is open is loosely fitted with an inner tube whose both ends are open. An underground heat exchanger having a structure in which the tip of a pipe is buried in the basement and air is passed through a gap between the inner pipe and the outer pipe to exchange heat with geothermal heat, and the length of the outer pipe is increased. A plurality of concave grooves having a cross-sectional shape extending to the bottom are formed, and the protrusions of metal blades having protrusions extending laterally are fitted into the concave grooves. A ground heat exchanger is disclosed.

  Patent Document 2 discloses an underground heat exchanger having a double tube structure in which an inner tube having both ends opened is loosely fitted to an outer tube having a sealed tip and the other end opened. The tip of the outer pipe is buried in the basement, air-conditioned air flows through the gap between the outer pipe and the inner pipe to exchange heat with geothermal heat, and then the air collides with the bottom of the outer pipe, An air-conditioning mechanism using a ground heat exchanger with a mechanism for making a U-turn through the inner pipe, storing water at the bottom of the outer pipe, and letting air flowing from the gap between the outer pipe and the inner pipe Disclosed is an air-conditioning mechanism using a ground heat exchanger, wherein dust or / and volatile organic compounds in the air are removed by colliding with the level of water stored at the bottom of the outer pipe. Yes.

JP 2007-183024 A JP 2007-303669 A

According to a known heat exchanger for air conditioning equipment as shown in FIG. 5, it is possible to use underground cold / heat without being affected by the seasons and weather, and at an extremely low running cost. Such heat exchangers for air conditioning equipment are welcomed by the air conditioning industry and are installed nationwide.
However, based on many years of research and experience, the inventor has confirmed that there is still room for improvement in the above-described conventional heat exchanger for air conditioning equipment. This point will be described in detail below.

In the heat exchanger for air conditioning equipment described above, as shown in FIG. 5, the air flow that is sent in the direction of arrow b and flows down in the inner pipe 3 in the direction of arrow c is between the soil and the soil. Do not exchange heat. The reason is that the inner pipe 3 is not in contact with the soil.
Therefore, the underground constant temperature is hardly utilized for the incoming air flow, and as a result, the difference between the temperature of the incoming air flow in the direction of arrow b and the temperature of the air flow reversed as shown by arrow d is It was only a reflection of heat exchange with water 4. That is, in the reciprocating path that is returned after being sent to several meters below the ground, only the rising air flow is heat exchanged with the soil, and the falling air flow is not heat exchanged with the soil. For this reason, the conventional heat exchanger for air conditioning equipment has a limit in terms of improving its heat exchange efficiency.

  The present invention has been made in view of the circumstances described above, and the object of the present invention is to provide a pipe that guides the air flow into the ground and a pipe that guides the air flow to the ground. It is to improve the heat exchange efficiency by improving the heat exchanger for air conditioning equipment that exchanges heat between the stream and soil.

  As a result of diligent studies to achieve the above-mentioned object, the present inventor allows heat to be exchanged with soil in the entire process of underground movement, in other words, the air flow that moves underground, in other words, The present inventors have found that heat exchange is performed with soil by bringing all tubular members that guide the air flow underground into contact with the soil, and the present invention has been completed based on such knowledge.

The configuration of the invention according to claim 1 based on the knowledge described above will be described as follows with reference to FIG. 2 corresponding to the first embodiment. In addition, in order to make contrast with drawing easy, the code | symbol of drawing is attached, but this code | symbol does not limit the technical scope of this invention as drawing.
A pipe that guides an air flow into the ground by providing a partition wall 7 along a plane passing through the center line (Z) of the main pipe in the main pipe 6 that is a tubular member forming the main body of the heat exchanger. And a conduit that guides the air flow to the ground, and communicates (Es) the end point (lower end) of the conduit that guides the air flow to the ground and the start point (lower end) of the conduit that guides the air flow to the ground. . According to the dictionary, “along” is lined up without leaving. In the present invention, “along a plane passing through the center line” means being in the vicinity of the center line.

In the invention according to claim 2, as illustrated in FIG. 3 (B), the flow path for guiding air into the ground and the flow path for guiding air to the ground are formed by tubular members having substantially the same diameter. The lower end of the downflow pipe 9 that is configured and is a tubular member that guides air into the ground and the lower end of the upstream flow pipe 10 that is a tubular member that guides air to the ground are connected and communicated by a pipe joint 11, or As illustrated in FIG. 4D, the connection is made by a horizontal tube 13 which is a horizontal tubular member.
In the present invention, that the tubular members are substantially equal in diameter means a dimensional relationship in which the other tubular member (thinner) cannot be inserted into one tubular member (thicker), and they are inserted independently of each other. It means no state.
The “horizontal tubular member” in the present invention does not need to be strictly “horizontal” in a surveying sense, and means “lateral”, but in other words, “the height difference between both ends of the tube” Is less than half the length of the tube.

  As illustrated in FIG. 3A, the invention according to claim 3 includes a set of a tubular member (for example, 12a) that guides air into the ground and a tubular member (for example, 12b) that guides air to the ground. A plurality of sets are provided, that is, the dividing pipe group 12 is provided.

As illustrated in FIG. 4B, the invention according to claim 4 is a downflow pipe 9 that is a pipe that guides an air flow into the ground, and an upstream pipe that is a pipe that guides the air flow to the ground. 10 is characterized in that at least one of them is not vertical but is inclined.
In the present invention, being inclined means not being perpendicular to the horizontal plane with respect to the earth.

When the invention according to claim 1 is applied, as shown in FIG. 1 and FIG. 2 corresponding to the embodiment, the main pipe 6 is divided into a vertically divided shape by the partition wall 7 so that the descending air is divided. The flow path (arrow h) and the flow path (arrow j) of the rising air flow are formed, and the falling air flow (arrow h) contacts the soil through the tube wall of the main body pipe 6 and the rising air. Since the flow (arrow j) also contacts the soil through the tube wall of the main body tube 6, both the descending air flow and the ascending air flow are heated or cooled simultaneously by heat exchange with the soil.
For this reason, compared with the conventional heat exchanger for air-conditioning equipment heated or cooled only one way, heat exchange efficiency rises markedly.
Furthermore, the partition wall 7 provided in the present invention exhibits an effect as a reinforcing member, and strengthens the main body tube 6.
For this reason, although the material strength is inferior to that of steel members, even if the main body tube 6 is formed of a light alloy such as aluminum having high thermal conductivity, the heat exchange efficiency is further improved without significantly reducing the rigidity. Can be made.
Moreover, the heat exchanger of the present invention can further improve the heat exchange efficiency when heat transfer ribs (fins) made of an aluminum alloy with good heat conduction performance are used in combination.

  The invention according to claim 2 has significance as an improved invention of the invention according to claim 1, and is commercially available without impairing the effects of “high heat exchange efficiency” and “high rigidity” in the invention according to claim 1. As a result, the manufacturing cost can be reduced and the product quality can be made uniform.

If the invention which concerns on Claim 3 is applied, an air flow can also be distribute | circulated in series with respect to the set of several tubular members installed, it can also distribute | circulate in parallel, and the switching use of a series and parallel is also possible. .
For this reason, there exists a practical effect that the design freedom degree of the whole heat exchanger for air-conditioning equipment is raised.

  When the invention according to claim 4 is applied, a desired air flow path length can be obtained even when, for example, the bedrock is 2 to 3 meters below the ground and the embedment depth of the heat exchanger is limited. .

It is the typical perspective view which showed two embodiment which concerns on this invention, and was partially broken and drawn. It is the typical front view which showed the state which installed the heat exchanger which concerns on this invention, and was partially cut and drawn. 2A and 2B show two exemplary embodiments according to the present invention, in which FIG. 2A is a schematic perspective view drawn by cutting out an intermediate portion, and FIG. 2B is a schematic perspective view drawn by partially breaking. It is the typical perspective view which fractured | ruptured partially and depicted the modification of above-mentioned FIG.3 (B). FIG. 5 is a schematic vertical sectional view depicting four examples of embodiments recommended when shallow rock is present. It is the figure which added the arrow for explaining operation | movement to the typical vertical sectional view which drew the state in which the heat exchanger for an air conditioning of a well-known example is installed.

FIG. 1A shows an embodiment of a heat exchanger according to the present invention. In this embodiment, for example, a vertically divided partition wall 7 is integrally formed in a main body tube 6 made of aluminum alloy.
Thereby, the internal space of the main body pipe 6 is divided into two, but the partition wall 7 is omitted from the lower end portion Es of the main body pipe 6, and the two divided spaces communicate with each other at the lower end portion. .
FIG. 2 shows a state where the members of the embodiment of FIG. 1 (A) are installed.
As shown in FIG. 2, the air flow (arrow a) sent from the blower 5 is guided to one space of the main body pipe 6 in the direction of the arrow g, flows downward in the direction of the arrow h, and flows into the main body pipe 6. Folds in the direction of the arrow i at the lower end Es, flows upward in the direction of the arrow j, and is discharged from the main body pipe 6 in the direction of the arrow k.
During this time, the air flow is always exchanged with the soil through the wall of the main pipe 6 during the downward flow indicated by the arrow h and during the upward flow indicated by the arrow j, so that it is cooled in the summer and heated in the winter. Being the optimal temperature for life.
When practicing the present invention, it is possible to apply a known technique (see FIG. 6) in which water is stored at the lower end portion of the main body pipe, but this is not always necessary.

FIG. 1B is a modification of the embodiment shown in FIG. In this embodiment, the basics of partitioning the inside of the main body pipe 6 into the vertically divided shape are the same as those described above, but are characterized in that the partition wall is formed in a cross shape.
In the embodiment of FIG. 2 configured using the members of FIG. 1A, a U-shaped flow path is formed as indicated by an arrow hij, but the embodiment of FIG. Then, two sets of U-shaped flow paths are formed.
When carrying out this embodiment, two sets of U-shaped flow paths can be connected in series to flow air, or air can be flowed in parallel.

FIG. 3A is a modification of FIG. In the embodiment of FIG. 1A, one main body pipe 6 is divided by a partition wall 7 to form an air descending flow path and an ascending flow path. However, in the embodiment of FIG. The downflow pipe 9 and the upflow pipe 10 were configured by arranging two pipes in parallel, and the lower ends of the respective pipes were connected and communicated by a pipe joint 11.
In this example, a commercially available aluminum alloy pipe (JIS standard product) was processed to create the downflow pipe 9 and the upflow pipe 10.
According to this example, since the mass-produced aluminum pipe material is used, the manufacturing cost is low, and since the standard product is used, the uniformity of quality is guaranteed.
Moreover, high heat exchange efficiency can be obtained due to the good thermal conductivity unique to the aluminum alloy.

The embodiment shown in FIG. 3B is a modification of the embodiment shown in FIG.
As can be understood by comparing the two drawings, the cross partition wall 8 of FIG. 1 (B) is divided into four parts that are cut together with the main body pipe 6, so that the divided pipes 12a to 12d of FIG. Is formed.
The lower end of the split pipe 12a and the lower end of the split pipe 12d are connected by a curved pipe 18 that functions as a pipe joint. Similarly, the lower end of the split pipe 12b and the lower end of the split pipe 12c are connected by a curved pipe 20 that functions as a pipe joint.
Furthermore, the upper end of the split pipe 12a and the upper end of the split pipe 12b are connected by a curved pipe 19 that functions as a pipe joint.
The air flow discharged from the blower 5 is guided to the dividing pipe 12d as indicated by an arrow m. The air flow that has finished flowing downward in the dividing pipe 12d is caused to flow into the curved pipe 18 to make a U-turn as indicated by an arrow n, and is guided to the dividing pipe 12a.
The air flow that has flowed upward in the dividing pipe 12a is made to make a U-turn again by the curved pipe 19, flows downward in the dividing pipe 12b, and flows into the dividing pipe 12c with a third U-turn as indicated by the arrow q. Then, it flows upward and is released as indicated by an arrow r.

In the embodiment shown in FIG. 3B, the air flow is divided into four divided pipes 12a to 12d.
Were circulated sequentially. That is, four dividing pipes were connected in series.
The embodiment shown in FIG. 4 can also be configured by using four divided pipes 12a to 12d similar to the above as main constituent members.
As shown in FIG. 4, the air flow discharged from the blower 5 in the direction of arrow “a” is divided by the branch pipe 17 as indicated by arrows g <b> 1 and g <b> 2.
The diverted air flow indicated by the arrow g1 flows into the dividing pipe 12a and flows downward in the direction of the arrow h1, and after the curved pipe 16 makes a U-turn once in the direction of the arrow i1, it is guided to the dividing pipe 12b and is indicated by the arrow j1. In the direction of and discharged in the direction of arrow k1.
On the other hand, the air flow indicated by the arrow g2 divided by the branch pipe 17 flows into the dividing pipe 12d and flows downward.
Although not shown, the lower end portion of the dividing tube 12d and the lower end portion of the dividing tube 12c are connected by the same member as the curved tube 16.
The air flow flowing through the dividing pipe 12d is made to make a U-turn only once as indicated by the arrow i2 (by the curved pipe (not shown)), flows upward into the dividing pipe 12c, and is discharged as indicated by the arrow k2. .
In both the embodiment of FIG. 3B and the embodiment of FIG. 4, each of the four split pipes 12a to 12d is buried in the ground, and its outer periphery is in contact with the soil. Both the stream and the descending air stream are heat exchanged with the soil. For this reason, high heat exchange efficiency is obtained.
Whether two sets of U-turn flow paths are connected in series as in the embodiment of FIG. 3B or whether two sets of U-turn flow paths are connected in parallel as in the embodiment of FIG. It is desirable to select in consideration of the condition of the house that is the target of the performance and the performance of the blower.

When practicing the present invention, it is desirable to embed at a depth of 4 to 5 meters underground under normal environmental conditions. However, depending on the state of the formation, a buried depth of 4 to 5 meters cannot be obtained. For example, it is a case where there is a bedrock near 3 meters underground.
FIG. 5 shows a preferred embodiment when the embedding depth is restricted by bedrock or the like.
As shown in FIG. 5A, when the bedrock R is in a shallow location, a plurality of downflow pipes 9 and a plurality of upflow pipes 10 are embedded. These downflow pipes 9 and upflow pipes 10 are structural members similar to those shown in FIG. 3A, and the lengths thereof are appropriately set according to the depth of the rock.
The downflow pipe 9 and the upflow pipe 10 are sequentially connected to form a W-shaped flow path as shown in FIG.
Thereby, the flow path length of multiple times is formed compared with the embedding depth of a heat exchanger, and desired heat exchange efficiency is obtained.

Since the bedrock exists in a relatively shallow part of the basement, the embodiment shown in FIG. 5B is suitable when the embedding depth is insufficient.
The downflow pipe 9 and the upflow pipe 10 similar to those in FIG. 3 (A) are embedded so as to be inclined as shown in FIG. 5 (B).
As a result, a flow path length that is a few percent higher than the embedding depth of the heat exchanger is formed, and a desired heat exchange efficiency is obtained.
Based on the same principle, two inclined pipes 14 may be embedded in a V shape as shown in FIG. This also forms a channel length that is a few percent higher than the embedment depth of the heat exchanger, and a desired heat exchange efficiency can be obtained.

If the bedrock is in a shallow location and the groundwater level is above the bedrock, the embodiment of FIG. 5 (D) is recommended.
The downflow pipe 9 and the upflow pipe 10 similar to those in FIG. 3A are embedded in a region above the bedrock R, and the lower end of the downflow pipe 9 and the lower end of the upflow pipe 10 are connected to the horizontal pipe 13. The connection is communicated by.
When the air flow through the tubular member exchanges heat with the outer material through the tube wall, the outer material is more water in the surrounding gravel than when the outer material is general earth and sand with normal moisture content. In some cases, the thermal contact is dense (low heat transfer resistance).
Thereby, heat exchange efficiency remarkably high compared with the embedding depth of a heat exchanger is obtained.

DESCRIPTION OF SYMBOLS 1 ... Floor 2 ... Outer cylinder 2a ... Heat transfer fin 3 ... Inner pipe 4 ... Reserved water 5 ... Blower 6 ... Main body pipe 7 ... Partition wall 8 ... Cross partition wall 9 ... Downflow pipe 10 ... Upflow pipe 11 ... Pipe joint DESCRIPTION OF SYMBOLS 12 ... Pipe group 12a-12d ... Divided pipe 13 ... Horizontal pipe 14 ... Inclined pipe Es ... Lower end part of outer cylinder R ... Rock bed S ... General earth and sand W ... Groundwater surface

Claims (4)

Heat for air conditioning equipment that has a conduit that guides the air flow to the ground and a conduit that guides the air flow guided to the ground to the ground, and allows heat exchange between the air flow and the soil. In the exchanger
By providing a partition wall along the surface passing through the center line of the main body tube in the main body tube, which is a tubular member that forms the main body of the heat exchanger, the pipe line that guides the air flow into the ground and the air flow are grounded And a conduit leading to
A heat exchanger for an air conditioner, characterized in that an end point of a pipe that guides the air flow into the ground and a start point of the pipe that guides the air flow to the ground are communicated. Heat for air conditioning equipment that has a conduit that guides the air flow to the ground and a conduit that guides the air flow guided to the ground to the ground, and allows heat exchange between the air flow and the soil. In the exchanger
The flow path for guiding the air to the ground and the flow path for guiding the air to the ground are constituted by tubular members having substantially the same diameter independent from each other.
In addition, the lower end of the tubular member that guides air to the ground and the lower end of the tubular member that guides air to the ground are connected and connected by a pipe joint or a horizontal tubular member. Heat exchanger.   The heat exchanger for an air conditioner according to claim 1 or 2, wherein a plurality of sets of a tubular member that guides air to the ground and a tubular member that guides air to the ground are provided. The air conditioning equipment according to claim 1 or 2, wherein at least one of a conduit that guides the air flow to the ground and a conduit that guides the air flow to the ground is inclined rather than vertical. Heat exchanger.

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